Like our morning egg, bacteria once endured a bad rap. For years, we were told to vigorously scrub off bacteria in the name of clear, luminous skin. Now, science suggests we might want to back away slowly from harsh cleansers, add bacteria to our face, and eat bacteria too.
The human body is host to something called the microbiome, which plays an essential role in homeostasis (keeping the body in balance). The microbiome consists of an estimated 100 trillion microbes, including bacteria, fungi, and viruses, the bulk of which live in the gut.
In recent years, researchers have been taking a long, hard, microscopic look at the human microbiome. They’ve realized that not all bacteria are germy, harmful, or unwelcome.
The gut and the skin: a special connection
The gut is the HQ of our body’s microbiome, but our skin plays host to microbes too. And like the rest of our body, skin effectively performs its functions—protection, temperature regulation, water retention, and more—when it’s in homeostasis. Our skin is colonized by an abundance of bacteria, and most of them are not just harmless; they’re beneficial.
The gut and skin microbiomes are inextricably linked and have a lot in common. “There are a lot of similar microorganisms that can be found in the gut and on the skin’s surface,” says Gretchen Frieling, MD, a board-certified dermatopathologist. “By balancing ‘good’ and ‘bad’ bacteria, your gut enables your skin to act as a barrier that prevents toxins and pathogens from entering the body. When both your gut and skin are healthy, your body will produce more anti-inflammatory molecules to fight skin conditions like acne, eczema, psoriasis, and rosacea.”
Indeed, research has found that an unhealthy gut microbiome can cause inflammatory manifestations in skin. A balanced microbiome, on the other hand, can reinforce skin so it can effectively offset factors that can “lead to redness, dryness, and a weakened surface that more rapidly shows signs of aging from environmental stressors,” according to Frieling.
Probiotics and prebiotics: eating for healthy skin
Factors like diet and stress can cause an imbalance in our microbiome, but the flip side is also true: We can regain balance by adding bacteria to our diet, specifically in the form of probiotics.
Probiotics are “friendly” live bacteria that benefit the body—most famously the digestive system. But their benefits extend beyond better digestion. In one study, people who took probiotic supplements for 12 weeks saw decreased transepidermal water loss (when water evaporates from skin, leaving it parched) and increased hydration. In another study, ingesting probiotics helped improve skin barrier function. A third study found that probiotic intake helped lower skin sensitivity.
Consuming prebiotics, a special form of dietary fiber that acts as a fertilizer for the good bacteria in your gut, is also important, says Frieling.
“You need a diet high in indigestible fiber (prebiotics) to feed the good bacteria in your gut; without a food source, probiotics can’t thrive,” she says. “If you take the probiotic (the bacteria) but don’t take the prebiotic (the food source), chances are you’ll have a difficult time keeping beneficial microorganisms.”
Applying probiotics to your skin
We used to believe we had to get our skin squeaky clean of dirt, oil, and bacteria. Now we know better—and there are skincare products teeming with bacteria.
Topical probiotics have been shown to increase ceramides (fat molecules naturally found in the uppermost layer of skin that help retain water) in subjects with eczema. Topical probiotics can also reduce the concentration of acne lesions and pathogenic bacteria, and they may reduce skin sensitivity in healthy people.
Keep in mind that probiotic skincare might not be for everyone. “Based on a series of ongoing research, these products are not intended for anyone who is immunosuppressed or has a low level of white blood cells,” cautions Frieling.
Just like us, our skin simply seeks balance. Whether that equilibrium arrives through probiotic supplements, probiotic skincare, or a diet with more fermented foods and prebiotics, once our skin finds its happy medium, it will calm down, get stronger, and radiate. And we’ll have our friendly neighborhood bacteria to thank. It’s a good thing bacteria saved its reputation.
Fantastic -biotics and where to find them
If you’re daunted by the idea of incorporating raw chicory root or Jerusalem artichoke (two illustrious prebiotics) into your diet, don’t be. You can find plenty of prebiotics in more common foods like bananas, leeks, onions, garlic, apples, and flaxseeds.
Before you invest in a probiotic product, identify which strains are included and ask the company about the research behind it. Certain strains of bacteria work better for different complexions, says dermatopathologist Gretchen Frieling, MD.
If your skin is thirsty, try popping a probiotic supplement with strains of Lactobacillus paracasei NCC 2461, which, studies have shown, can strengthen the skin barrier and improve hydration levels.